


Switching it Up

by waterbird13



Series: Tumblr Fics [295]
Category: Supernatural
Genre: Bottom Dean, Bottom Sam, M/M, Multi, NSFW, Polyamory, Top Benny, Top Sam, first time threesome
Language: English
Status: Completed
Published: 2016-10-30
Updated: 2016-10-30
Packaged: 2018-08-28 00:23:31
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 855
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/8423524
Author URL: https://archiveofourown.org/users/waterbird13/pseuds/waterbird13
Summary: Dean loves to be filled, Sam loves filling him.Adding a third person to their relationship means thinking of new ways to configure themselves.





	

****

The big secret is that Dean loves to be filled. Fingers, toys, and especially cock. It’s a secret Sam’s known for several years now, and he’s done his best to give Dean exactly what he wants.

Sam has a big dick and he knows exactly what to do with it, and he’s kept Dean happy for years. Neither of them has ever suggested changing things up.

No one, that is, until Benny.

Benny and Dean slept together in Purgatory, and Sam knows it. When they get back, Dean spends a great deal of time and effort trying to integrate all three of them into one relationship. Sam knows he’s the last hold out, but he finally gives in, agrees to give it a try. For Dean.

They end up in bed together that night, on Dean’s memory foam mattress. Benny gestures to the bed. “Lemme see ya two,” he says, eyes hungry. So Sam and Dean strip each other, and Sam pushes Dean onto the bed.

Sam isn’t in the mood to screw around, wants to drive Dean absolutely wild, make him come like a geyser. It’s stupid, but Sam knows it has too much to do with staking his claim for the idea to be strictly comfortable.

He sucks bruises into Dean’s spread, delicate inner thighs while he opens him up on fingers, first one, then two, then three, making Dean thrash and curse.

He finally gives in to what he knows Dean wants and fills him up, giving him exactly what he craves so desperately, stuffing him full and brushing his prostate on each thrust. Dean claws at Sam’s back and Sam groans, little sparks of pain pushing him on.

It feels like every other perfect time, except…

“Benny, what the fuck?” Sam gasps.

Benny trails his slicked-up finger around Sam’s rim. “Ya mind, Sugar?” he asks. “Feel like gettin’ in on the action.”

“Sam doesn’t– _fuck–_  bottom,” Dean gasps.

It’s not strictly true. Sam’s played with his own ass before, just to test it out. Dean’s even rimmed him before a couple of times. He liked it. He’s _thought_  about it. _Fuck it,_  he thinks. “Go ahead,” he says. “Slow.”

“Be real careful, Sugar,” Benny promises lowly, gently pressing that first finger against the muscle.

“ _Fuck_ ,” Sam gasps when Benny presses the finger inside.

“Feels good, doesn’t it?” Dean asks.

Sam growls. “If you’re talking, I’m not working hard enough,” he says, beginning to pump his hips faster, harder, making Dean cry out and cling to him.

Benny begins working that one finger into Sam in earnest, then slowly adds a second one. It’s moved from feeling weird to beginning to feel _good_ , and Sam hazily thinks that he should have done this more often.

Sam needs both hands to support his weight, between fucking Dean and Benny’s onslaught, so he doesn’t have a hand free to help out an increasingly desperate Dean. Fortunately, it doesn’t seem to be necessary. A cock in Dean’s ass is often enough, and this time is no exception.

Dean lets out breathy little moans when he comes. His eyes fall closed and he digs his nails even deeper into Sam’s shoulders. Sam keeps pumping into him through it, then makes himself stop as soon as Dean’s squirming turns uncomfortable. He pulls out, as gently as he can considering Benny is still repeatedly stroking his prostate, three fingers in Sam now.

Sam repositions himself to make this easier, pushing his ass back, wanting. Dean touches his face. “You like this,” he marvels.

“Ngh,” is all Sam can get out, considering Benny’s dick is now pressing against his ass, spreading him wide. Dean tugs him into a kiss as Benny pushes into him.

Sam grips the sheets tight. It _hurts_ , but it also feels good beneath that, the pain already receding. Benny hesitates a moment, then begins to fuck him.

“Dean, _Cher_ , come ‘ere an’ watch your brother take a dick,” Benny says. Dean scrambles over, and Sam moans as Benny pushes into him just right.

“Fuck,” Dean says. “Looks so good.”

“Hell yeah,” Benny grunts. “’M close, Sam. You close?”

Sam is. He shifts his weight so he can have a hand free to stroke himself off. Benny picks up his pace, and it only takes a handful of strokes before Sam’s coming, Benny hot on his heels.

Sam collapses face first into the bed as soon as Benny pulls out, groaning into the pillow.

He feels eyes on his ass. “Goddamn,” Dean says, voice low and rough. “I want…holy hell. Sam, I wanna make you look like this. Gonna let me?”

Sam hums agreeably, too worn out for words to convey how into having this happen again he is.

Benny doesn’t seem to have that problem. “Think he will,” he muses. “I wanna see it. An’ I wanna fuck you. An’ who knows. Maybe you two could fuck me. Might be nice. Mix it up a bit.”

Sam groans, still face-first in the mattress. This relationship, he thinks hazily, was a goddamn fantastic idea, and he doesn’t know why on earth he ever thought otherwise.


End file.
